A railcar acoustic monitoring system including a first trackside frame assembly that includes a first outer frame assembly, a second outer frame assembly, and a first inner frame assembly. The first outer frame assembly including a first microphone assembly positioned on a first outer side of the first rail of the railroad track, the first microphone assembly oriented to receive acoustic signals associated with the passing train. The second outer frame assembly including a second microphone assembly positioned on a second outer side of a second rail of the railroad track, the second microphone assembly oriented to receive acoustic signals associated with the passing train. The first inner frame assembly including a first housing, a third microphone assembly oriented to receive acoustic signals emanating from the first rail, and a fourth microphone assembly oriented to receive acoustic signals associated with the passing train.

A railcar acoustic monitoring system including a first trackside frame assembly that includes a first outer frame assembly, a second outer frame assembly, and a first inner frame assembly. The first outer frame assembly including a first microphone assembly positioned on a first outer side of the first rail of the railroad track, the first microphone assembly oriented to receive acoustic signals associated with the passing train. The second outer frame assembly including a second microphone assembly positioned on a second outer side of a second rail of the railroad track, the second microphone assembly oriented to receive acoustic signals associated with the passing train. The first inner frame assembly including a first housing, a third microphone assembly oriented to receive acoustic signals emanating from the first rail, and a fourth microphone assembly oriented to receive acoustic signals associated with the passing train.

Prior to manufacturing a product by additive manufacturing, a stress relief profile including frequency and amplitude parameters of an ultrasonic input is determined based on physical properties of the product, including resonant frequencies of the product and a material from which the product is manufactured. Successive layers of a material are added and energy is applied to incorporate the material of each layer into the product. A processor accesses stress relief profile parameters for each layer, determines whether a layer requires stress relief and determines a frequency and a power level for the stress relief at the layer. An ultrasonic input is applied with the determined parameters to relieve stress as the product is built up.

A process for detecting the presence and position of defects in metal bars can include: measuring the velocity of longitudinal sound propagation in a metal bar; acquire the Fourier spectrum of an intact, defect-free metal bar comprised of the same composition structural and length as metal bar under examination; comparing the Fourier of the metal bar and a metal bar having similar composition and length; and in response to presence of any extra spectral lines due to the presence of defects in the metal bar under examination, identifying the frequency f of said extra spectral lines and obtaining the distance x of a defect from one end of the metal bar under examination.

A process for detecting the presence and position of defects in metal bars can include: measuring the velocity of longitudinal sound propagation in a metal bar; acquire the Fourier spectrum of an intact, defect-free metal bar comprised of the same composition structural and length as metal bar under examination; comparing the Fourier of the metal bar and a metal bar having similar composition and length; and in response to presence of any extra spectral lines due to the presence of defects in the metal bar under examination, identifying the frequency f of said extra spectral lines and obtaining the distance x of a defect from one end of the metal bar under examination.

The present disclosure discloses a flexible substrate and a fabrication method thereof, a method for detecting a bend, and a flexible display device. A flexible substrate includes a flexible base, and a surface acoustic wave generating element and a surface acoustic wave detecting element positioned on the flexible base. The surface acoustic wave generating element and the surface acoustic wave detecting element are configured to detect a bend of the flexible substrate.

The present disclosure discloses a flexible substrate and a fabrication method thereof, a method for detecting a bend, and a flexible display device. A flexible substrate includes a flexible base, and a surface acoustic wave generating element and a surface acoustic wave detecting element positioned on the flexible base. The surface acoustic wave generating element and the surface acoustic wave detecting element are configured to detect a bend of the flexible substrate.

A settling basin of a wastewater treatment system includes a collector chain including chain links having a plurality of side bars, stepped connecting pins configured to join the plurality of side bars and including a first end including a head portion having a cross-sectional area larger than portions of the plurality of side bars through which the stepped connecting pin extends, end caps configured to receive second ends of the stepped connecting pins, and apertures defined in the end caps and second ends of the stepped connecting pins configured to receive a retaining element that holds the end caps in position on the second ends of the stepped connecting pins.

The present disclosure discloses a flexible substrate and a fabrication method thereof, a method for detecting a bend, and a flexible display device. A flexible substrate includes a flexible base, and a surface acoustic wave generating element and a surface acoustic wave detecting element positioned on the flexible base. The surface acoustic wave generating element and the surface acoustic wave detecting element are configured to detect a bend of the flexible substrate.

The present disclosure discloses a flexible substrate and a fabrication method thereof, a method for detecting a bend, and a flexible display device. A flexible substrate includes a flexible base, and a surface acoustic wave generating element and a surface acoustic wave detecting element positioned on the flexible base. The surface acoustic wave generating element and the surface acoustic wave detecting element are configured to detect a bend of the flexible substrate.